Non-universality of dephasing in quantum transport

We investigate the influence of the environment on coherent quantum transport. While random processes with classical stochastic potentials can be treated in the concept of phase memory, this is not possible for fully quantized system-plus-reservoir models. In the latter case, the decay of coherences is not only depending on the coupled dynamics, but also crucially on the special geometry of the physical system in regard. We introduce a microscopic model with localized environmental modes where the geometry dependence is removed and calculate the coherence length.